Foreach loop echo

Question

The last foreach loop doesn't seem to echo the list I want, it doesn't print anything. How can I fix this? I know it's getting quite complicated but any help would be appreciated.

$allTroopsList = array();
$allMissionsList = array();
while ($mytroops = $alltroops->fetch_assoc()) 
{
    $allTroopsList []= $mytroops;
}

while ($mymissions = $allmissions->fetch_assoc()) 
{
    $allMissionsList []= $mymissions;
}

while($userintroop = $allUsersintroops->fetch_assoc()) 
{
    if($userintroop['userid'] == $_SESSION['userid']) 
    {
        echo "<ul class='troop'>";   
        echo "<li>" . $userintroop['troopid'].  " </li>";
        foreach($allTroopsList as $mytroops) 
        {
            if($userintroop['troopid'] == $mytroops['troopid']) 
            {
                echo "<li> Troop description: " . $mytroops['description'].  " </li>";

                foreach($allMissionsList as $mymissions) 
                {
                    if($mytroops['missionid'] == $mymissions['missionid']) 
                    {   
                        echo "<li> Missionname: " . $mymissions['missionname'].  " </li>";
                        echo "<br/>";
                        echo "</ul>";
                    }
                }
            }
        }
    }   
}           

foreach($allUsers as $myotherusers) 
{
    if($userintroop['userid'] == $myotherusers['userid']) 
    {

        echo "<li> other users: " . $myotherusers['username'].  " </li>";
        echo "<br/>";
    }
}

Answer 1

This line:

while($userintroop = $allUsersintroops->fetch_assoc()) 

is fetching results from a database, right? That'd mean at some point you run out of rows to fetch, and $userintroop will become a boolean FALSE.

Then later on you try to do

if($userintroop['userid'] == $myotherusers['userid']) 

which is wrong on two levels - $userintroop will NOT be an array at this point, so it could never have a ['userid'] parameter. And since it's the result of a failed fetch operation, never could have any value OTHER than a FALSE.

So that last loop does execute, but will never produce anything since the conditions for producing output are literally impossible to meet.